SU370376A1 - ELECTRO-HYDRAULIC RELAY NEXT - Google Patents

Description

an initial state sensor 14 serving to prepare the system for operation.

In the case of the electrohydraulic relay unit W, two freely interlocking two-position three-edged poles of 15 and 16 are mounted, controlled by electromagnets 17, 18, 19 and 20 of the pushing action. The normal position of both spools corresponds to their upper position in the drawing, so the electromagnets 18 and 20 are included. Each spool has two normally closed working slots (upper ones in the drawing) and one normally open working slot. The magnitude of the total stroke of the spool is such that when opening the working slots, the saturation mode of the flow rate is set, and When shutting off, the hydraulic lines are reliably locked. Half of the general move comes at the opening of the highways, half at the presidency.

The binary five-bit counter 5 and the quantization unit b according to the level of the positive direction (FIG. 2) include the logic circuit OR 21, the logic circuits AND 22 and 23, the gates 24, 25 and 26.

The forced switching unit 8 of the positive direction (see Fig. 3) includes a trigger 27 with inputs 28 and 29, an auxiliary trigger 30, transistors 31-39, resistances 40 and 41, a capacitor 42, an impulse transformer 43, thyristors 44 and 45.

The scheme of the forced switching unit 9 of the negative direction is similar to the scheme of the block 8.

In the tracking mode, program pulses from an interpolator or from a magnetic tape of a program block / after synchronization with AI frequency from clock generator 4 are sent to one of the inputs of a binary reversing counter 5. In addition, feedback pulses and synchronization are received to the input of a reversing counter by frequency Do . Thus, the number of pulses contained in the meter is a system error in pulsed form. If the error exceeds the positive insensitivity limit (necessary for the relay system under the condition of M stability), the 1PO quantization unit with the positive direction level 6 opens the output channel 28 to the amplifier 8 forced switching unit of the amplifier electromagnets and supporting them. In open channel 28, block 8 passes a regular clock pulse B from clock generator 4, electromagnet 17 of electrohydraulic relay block 10 is activated, the cylinder of hydraulic cylinder 11 moves in the full direction until the pulses from the feedback sensor change the state of the reversible counter in a way that the decreasing error goes beyond the positive insensitivity boundary in the opposite direction. After that, the quantization unit at level 6 closes the channel 28 and opens the channel 29 of the output to the forced switching unit 8. The open "channel 29 in block 8 will pass the next impulse of the clock frequency B from the clock pulse generator 4, the electromagnet 18 of the electro relay relay-block 10 is triggered, the piston rod of the hydraulic cylinder 11 moves in the negative direction (opposite to the arrow) The status of the reversible counter does not change in such a way that the decreasing error goes beyond the negative insensitivity boundary in the opposite direction. Thereafter, the level 7 quantization unit closes the channel 28 and opens the output channel 29 to the forced switching unit 9. The open channel 29 passes a regular clock pulse B from the clock pulse generator, the electro-hydraulic relay unit 10 is triggered, and the hydraulic cylinder // pumps will turn out to be locked.

Thus, when a pulse appears in channel 28, block 8 connects the coil of the electromagnet / 7 to a high voltage source. The anchor of the electromagnet 17 in less than 0.001 seconds moves the spool 15 to the lower position, after which the voltage applied to the electromagnet 17 decreases to the level of a loderder; As soon as the spool 15 is in the lower position, the pump line is connected to the left cavity of the hydraulic cylinder 11, and the right cavity is connected to the tank through the line 47. The hydraulic cylinder piston moves in the direction of the arrow with the maximum possible acceleration. When a pulse appears in channel 29, block 8 removes support bushing from an electromagnet 17 coil and connects an electromagnet 18 to a high voltage source. The spool 15 moves to the upper position, after which the voltage applied to the electromagnet 18 coil decreases to the support level . The pass line 46 is connected through successively open working slots of the spools to the tank, and the pump is discharged. At the same time, both cavities of the hydraulic cylinder // are locked and the piston brakes to a full stop until the next impulse in channel 28 causes the thrusters to move down again to 15. The rod of the hydraulic cylinder 11 is moved both by moving the spool 15 from top to bottom and from bottom to top. If a continuous sequence of pulses of a positive direction program arrives at the system input, the system operates in the so-called sliding mode. In this case, the relay spool 15 is continuously switched, and the spool 16 is in the upper position and a sequence of flow pulses enters the hydraulic cylinder with parameters depending on the characteristics of the system and the frequency of the input signal pulses. Due to the fact that with each displacement of the spool 15, slots with large flow areas are opened, throttle losses are minimized, the system works

in saturation mode. The higher speed of the spool movement makes it possible to open or close the liquid supply channels immediately after receiving the command pulse, as a result of which an almost inertia-free communication of the electronic control system with the hydraulic actuator is created.

The operation of the system when applying control pulses to the input of unit 9 is similar, and the control impulse in channel 28 causes the displacement of the hydraulic cylinder 1 against the arrow.

The initial state of the counter 5 (see Fig. 2) corresponds to the memorization of the number 15 (state 01111) and the number 16 (state 10000), with this, the relay tracking system is inside the deadband and the control commands to the actuator are not is served. If the number of pulses at the entrance to the counter exceeds 16, a command is given to move in the positive direction; if the number of pulses is less than 15, the command to move in the negative direction is given. Certain commands, depending on the state of the counter, are supplied by a quantization unit by level. The AND circuit 22 operates in any state of the reversible counter, exceeding 10,000 (i.e. the number 16). When THIS.M opens the gate 24 of the output of the clock pulses of frequency BB channel 28 to block 8, which leads to the inclusion of the electromagnet 17 after the appearance of the first pulse, and the system starts to move. As soon as the state of the counter returns to the limits of the sensitivity zone (state 10000), the circuit 22 will no longer support the open valve 24, the circuit 23 triggers and the valve 25 of the output of the clock pulses of frequency B in channel 29 opens to block 9. As a result, The first pulse in channel 29 is turned off. The electromagnet 17 and the electromagnet 18 is turned on, the system stops. .

The quantization unit with respect to the level of the negative direction 7 is constructed similarly.

The input element of the control unit 8 by turning on the electromagnets is a trigger 27 with two inputs 28 and 29. When the next opening pulse is applied to the input 28

the transistor 32 is closed and the voltage of the source is removed from the load 40, which through the resistance 41 is applied to the base of the support transistor 33. The latter is unlocked simultaneously, but giving a signal to open the thyristor starting transistor 34. When the transistor 33 is opened, a current flows through the coil of the electromagnet 17 chain support (o in) - (30 in). The opened thyristor 44 forms the charge circuit of the capacitor 42: (+300 V) - (-300 V), thereby setting the forced acceleration of the electromagnet 17. When the charge of the capacitor 42 is terminated, the thyristor 44 is locked. Supported by the trigger in the open state, the support transistor 33 ensures that the support current passes through the coil of the electromagnet 17 before the arrival of the closing pulse at the input 29 of the control unit. Simultaneously with the opening of the thyristor 44, the winding of the pulse transformer 43 is supplied with a control signal to the auxiliary trigger 30, which locks the transistor supporting 37 of electromagnet 18 for the entire time that the support of electromagnet 17 is turned on. When the switching pulse to input 29 opens, transistors 32 and thyristor 45. The remaining circuit elements are locked. A powerful current pulse is passed through the coil of electromagnet 18 and the support current is turned on. A pulse is created when the capacitor 42 is discharged, which prepares the capacitance for a new charge when the next pulse and the pulse are received at the input 28.

35t-t

Subject invention

Elbtrohydraulic relay track system, with a comparison unit and a direct hydraulic engine control circuit, for example, for

40 machine tools with numerical control, characterized in that, in order to improve its dynamic characteristics, the direct circuit is made in the form of a digital quantization unit of a sublevel with control signals in a pulsed form and outputs of the positive and negative directions and switching off the flow connected to the block of forced switching of electromagnets of their amplifier 50 of support.